Here is a little glimpse at the guide by
06. Modelling the city structure
Buildings are built up one by one
The next step is all about replacing the created basic objects with real objects. Here, all of the gathered reference photos come in handy. A lot of people say that it’s better to work on the whole picture at once, but I like to focus on each individual element at a time. In this case, I make building after building (as the numbers on the illustration show) and make sure that they match more or less stylistically to one another.
07. Basics and rhythm
Rudimentary shapes can be used repeatedly
It’s vital to use the Array/Modifier function to create buildings in 3D. Create as many repetitive assets as possible: ledges, ornaments, pillars, windows and doors. In architecture, many elements are simple primitive shapes multiplied many times. The more recurrent assets are created at the beginning, the faster work will be in the future.
Make sure to read the whole breakdown here.